This disclosure is generally directed to photoreceptors, photoconductors, and the like. More specifically, the present disclosure is directed to rigid, multilayered flexible, belt imaging members, or devices comprised of an optional supporting medium like a substrate, at least one of a photogenerating layer and a charge transport layer containing a thiophthalimide, including a plurality of charge transport layers, such as a first charge transport layer and a second charge transport layer, an optional adhesive layer, an optional hole blocking or undercoat layer, and an optional overcoating layer. At least one in embodiments refers, for example, to 1, to from 1 to about 10, to from 2 to about 7; to from 2 to about 4, to 2, and the like. Moreover, the thiophthalimide, can be added to the photogenerating layer or to at least one of the charge transport layers and, for example, instead of being dissolved in the charge transport layer solution, the thiophthalimide can be added to the charge transport mixture as a dopant, and more specifically, the thiophthalimide can be added to the bottom charge transport layer.
Yet more specifically, there is disclosed a photoconductor comprised of a supporting substrate, a thiophthalimide containing photogenerating layer, or a thiophthalimide containing a charge transport layer or charge transport layers, such as a first pass charge transport layer, a second pass charge transport layer, or both the first and second pass charge transport layers to primarily permit improved ghosting characteristics, excellent photoconductor photosensitivities and an acceptable, and in embodiments, a low Vr; and minimization or prevention of Vr cycle up.
A number of advantages are associated with the photoconductors disclosed as indicated herein, and in embodiments, for example, increased photogenerating pigment sensitivity, minimal ghosting, especially as this ghosting is applicable to paper edge ghosting (PEG), and extended lifetimes. Additionally, in embodiments the photoconductors disclosed herein possess in embodiments excellent, and in a number of instances low Vr (residual potential), and allow the substantial prevention of Vr cycle up; high sensitivity; and low acceptable image ghosting characteristics. When a photoconductor is selectively exposed to positive charges in a xerographic print engine, such as the Xerox Corporation iGEN®, some of these charges may enter the photoconductor and manifest themselves as a latent image in the next printing cycle. This print defect may in some instances cause a change in the lightness of the half tones, commonly referred to as a “ghost” that is generated in the previous printing cycle.
A stream of positive charges may be emitted from the transfer corotron. Since documents like paper sheets are situated between the transfer corotron and the photoconductor, the photoconductor is shielded from the positive ions originating from the paper sheets. In the areas between the paper sheets, the photoconductor is fully exposed, thus in this paper free zone the positive charges may enter the photoconductor. As a result, these charges cause a print defect or ghost in a half tone print especially when there is a change to a larger paper format that covers the previous paper print free zone.
Also disclosed are methods of imaging and printing with the photoconductor devices illustrated herein. These methods generally involve the formation of an electrostatic latent image on the imaging member, followed by developing the image with a toner composition comprised, for example, of thermoplastic resin, colorant, such as pigment, charge additive, and surface additive, reference U.S. Pat. Nos. 4,560,635; 4,298,697 and 4,338,390, the disclosures of which are totally incorporated herein by reference, subsequently transferring the image to a suitable substrate, and permanently affixing the image thereto. In those environments wherein the device is to be used in a printing mode, the imaging method involves the same operation with the exception that exposure can be accomplished with a laser device or image bar. More specifically, flexible belts disclosed herein can be selected for the Xerox Corporation iGEN3® machines that generate with some versions over 100 copies per minute. Processes of imaging, especially xerographic imaging and printing, including digital, and/or color printing, are thus encompassed by the present disclosure. The imaging members are in embodiments sensitive in the wavelength region of, for example, from about 400 to about 900 nanometers, and in particular from about 650 to about 850 nanometers, thus diode lasers can be selected as the light source. Moreover, the imaging members of this disclosure are useful in high resolution color xerographic applications, particularly high speed color copying and printing processes.